Speaker Mounting Depth

I know that the speakers in my 2002 cavalier are 4x6 in front and 6x9 in back. Does anybody know the mounting depth there is? I'm not too sure of where its measured from in back and I'd rather not take apart the car more than once as I've never done it before.

Enter your vehicle information into this site. It will tell you everything you want to know and will need for the install.

http://www.crutchfield.com/cgi-bin/autoinfo/autoinfo.asp?lp=%2fapp%2fCar%2fMyCar.aspx